Scleral depressor

ABSTRACT

A remotely controllable system and method for positioning and operating a scleral depressor. A track is positioned to encircle at least a portion of the eye. One or more independent thrusters, or actuators, are radially positionable about the eye. An actuator is selectively deployable and selectively retractable by remote control. Thrusters may be mechanically operated and include pneumatic, hydraulic, electrical, chemical or other power supply forces. Remote control is provided by hand-operated controls, foot-operated switches or voice-operated control. A light source is positioned about at least a portion of the eye to provide transcleral illumination.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.10/735,268, filed Dec. 12, 2003, which claims priority to U.S.Provisional Patent Application Ser. No. 60/433,119, entitled SCLERALDEPRESSOR, filed Dec. 13, 2002 the entire specification of which ishereby incorporated by reference.

This document claims priority to U.S. Provisional Patent ApplicationSer. No. 60/466,630, entitled ILLUMINATED SCLERAL DEPRESSOR, filed Apr.30, 2003, the entire specification of which is hereby incorporated byreference.

TECHNICAL FIELD

This invention relates generally to ophthalmic surgical and examinationsystems and methods, and particularly, but not by way of limitation, toa method of depressing the sclera.

BACKGROUND

Ophthalmic surgeries of the retina are often complicated by optical andphysical barriers. For example, the anatomy and optical properties ofthe eye may obscure or obstruct the surgeon's view, particularly of theperipheral retina. The zone behind the iris (the colored portion of theeye) is obstructed from direct view. Consequently, the surgeon sometimesfinds it helpful to have an assistant manually apply pressure or“depression” to the outside of the eye in order to bring the retina intoadequate view to facilitate surgical manipulation.

Exemplary surgical techniques for which depression of the sclera may behelpful include removal of scar tissue and peripheral vitreous, laserphotocoagulation techniques, addressing retinal tears or breaks andothers.

The technique of manually applying pressure to the eye is not withoutproblems. Assistants may be inexperienced or unable to properly applypressure to aid the surgeon in visualization of the important peripheralpathology. Unexpected movement by the assistant may also cause problemsfor the surgeon and may be dangerous.

Furthermore, poor lighting of the surgical field often leads tocomplications during delicate intraocular surgical procedures. Forexample, inadequate lighting often impairs identification of smallperipheral retinal breaks or tears.

For these and other reasons, what is needed is a method and system toallow a surgeon to control application of pressure to the sclera andimprove visualization of the peripheral retina.

SUMMARY

An automated scleral depression system provides remote control of ascleral depressor. The scleral depressor can be positioned and actuatedby a surgeon or assistant. In one embodiment, a foot operated control iscoupled to a depressor and allows specific control of an actuator orlight. In one embodiment, a hand operated control is coupled to adepressor and allows specific control of an actuator or light. In oneembodiment, a voice operated control is coupled to a depressor andallows specific control of an actuator or light. In one embodiment, amicrophone is coupled to a processor and voice commands are used todirect the positioning and actuation of the scleral depressor or light.In one embodiment, a flexible cable is used to direct the positioningand actuation of the scleral depressor or light.

The present subject matter allows lateral displacement, or depression,of the wall of the eye to facilitate surgical procedures. A thruster, ordepressor component, provides the lateral mobilization. In oneembodiment, a remote control allows selection of the radial position ofone or more thrusters. In one embodiment, a remote control allowsselection of lateral mobilization of a selected thruster.

In one embodiment, a thruster is deployed, or retracted, by applying arotational force to a shaft within a lumen encircling at least a portionof an eye and the thruster is radially positioned by extracting, orinserting, the shaft within the lumen. In one embodiment, deployment andretraction are controlled by extracting or inserting a shaft within thelumen and radial position is controlled by rotating the shaft.

This summary is intended to provide a brief overview of some of theembodiments of the present system, and is not intended in an exclusiveor exhaustive sense, and the scope of the invention is to be determinedby the attached claims and their equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, like numerals describe substantially similar componentsthroughout the several views. Like numerals having different lettersuffixes represent different instances of substantially similarcomponents.

FIG. 1A illustrates an introducer fitted with a tube according to oneembodiment of the present subject matter.

FIG. 1B illustrates an introducer fitted with a sleeve and positionedabout an eye.

FIG. 2 illustrates an introducer positioned near a pig model eye.

FIG. 3 illustrates an introducer positioned on a pig model eye.

FIG. 4 illustrates a cut-away view of a balloon segment.

FIG. 5 illustrates a cut-away view of a track segment with a sleeve.

FIG. 6 illustrates a slotted tube segment.

FIG. 7A illustrates a balloon type thruster sheathed in a protectivesleeve.

FIG. 7B illustrates a deployed balloon type thruster.

FIG. 7C illustrates a sectional view of a balloon type thruster in adeflated mode.

FIG. 7D illustrates a sectional view of a balloon type thruster in adeployed mode.

FIG. 8 schematically illustrates a foot control, audio control and handcontrol coupled to a processor controlled scleral depressor.

FIG. 9 illustrates a foot controller for position and displacementcontrol of a particular thruster.

FIG. 10 schematically illustrates a thruster having articulating leversrelative to an eye.

FIG. 11 schematically illustrates a threaded thruster relative to aneye.

FIG. 12 schematically illustrates a telescoping cylinder thrusterrelative to an eye.

FIGS. 13A and 13B schematically illustrate an inflatable thrusterrelative to an eye.

FIG. 14 schematically illustrates a flexible drive shaft operated radialpositioning apparatus relative to an eye.

FIG. 15 schematically illustrates a ring gear and pinion drive operatedradial positioning apparatus relative to an eye.

FIGS. 16A, 16B and 16C illustrate an articulating link thruster.

FIG. 17 illustrates a thruster having a two lever scissors arrangement.

FIG. 18 illustrates a shape memory material thruster.

FIGS. 19A and 19B illustrate a cam actuated thruster.

FIG. 20 illustrates a thruster having independently operablearticulating mechanical links.

FIG. 21 illustrates a section view of a transcleral illuminator track.

FIG. 22 illustrates a track coupled to a light source.

FIG. 23 illustrates a double loop track relative to an eye.

FIG. 24 illustrates an introducer with speculum blades.

FIG. 25 illustrates a bell crank operated thruster.

FIG. 26 includes an illuminated portion of one embodiment of the presentsubject matter.

FIG. 27A includes a balloon portion of one embodiment of the presentsubject matter.

FIG. 27B includes a balloon portion of one embodiment of the presentsubject matter.

FIG. 28 includes a section view of a fiber optic element portion of oneembodiment of the present subject matter.

FIG. 29 includes a view of a double ended fiber optic element portion ofone embodiment of the present subject matter.

FIG. 30A includes a view of a two-lumen track with a spring elementaccording to one embodiment of the present subject matter.

FIG. 30B includes a section view of a track with a spring elementaccording to one embodiment of the present subject matter.

DETAILED DESCRIPTION

In the following detailed description, reference is made to theaccompanying drawings which form a part hereof, and in which is shown byway of illustration specific embodiments in which the invention may bepracticed. These embodiments are described in sufficient detail toenable those skilled in the art to practice the invention, and it is tobe understood that the embodiments may be combined, or that otherembodiments may be utilized and that structural, logical and electricalchanges may be made without departing from the spirit and scope of thepresent invention. The following detailed description is, therefore, notto be taken in a limiting sense, and the scope of the present inventionis defined by the appended claims and their equivalents.

An axis directed from anterior to posterior and passing through thecenter of the eye is referred to herein as the longitudinal axis.Distances from the longitudinal axis are described as having a lateralposition. Radial position refers to orientation about the longitudinalaxis. Thus, if the eye is considered to be at the center of a clockface, each of the twelve hour marks has a different radial position, allhaving the same lateral distance from the longitudinal axis, hereinrepresented by the shaft on which the clock hands are affixed. Forexample, the nose side of the right eye can be referred to as the 3o'clock position. At any particular clock hour (or radial) position, athruster can be extended to a high depression position meaning that thelateral dimension from the thruster to the longitudinal axis is small.In addition, a low depression position refers to a greater lateraldimension between the thruster and the longitudinal axis. Radialextension refers to a lateral dimension along a particular radial.

FIG. 1A illustrates a perspective view of introducer 95A adapted for usewith one or more thrusters in accordance with one embodiment of thepresent subject matter. Legs 100A and 100B are tubular and joined bywelded strut, or plate 125. In one embodiment, legs 100A and 100B arefabricated of stainless steel and plate 125 is fabricated of stainlesssteel sheet metal. In one embodiment, a nipple 105 is fixed to an end ofeach of legs 100A and 100B. In one embodiment, legs 100A and 100B arecoupled together with a flexible joint to allow the legs to beindividually manipulated to facilitate introduction of a track, orcurvilinear guide, about the bony orbit of the eye.

Introducer 95A facilitates introduction of a track, or ring, around atleast a portion of the eye, or globe. The track includes one or morecurvilinear guide that at least partially encircle the eye. In oneembodiment, the track includes an internal tube having a slot and aprotective outer sheath or sleeve. One or more thrusters are positionedwithin the track as described more fully elsewhere in this document. InFIG. 1A, internal tube 120 is looped and threaded through the lumen ofboth leg 100A and leg 100B. In the figure, a single loop is illustrated,however, additional loops may also be used. In various embodiments, theplacement of a thruster or light source about the bony orbit of the eyeis guided by either tube 120 or track 110. Balloon 115 is shown to beinflated in the figure.

In one embodiment, nipple 105 is adapted to receive an end of track 110,as shown in FIG. 1B. Track 110, in the embodiment illustrated, includesa plastic tubular ring. Track 110, when positioned for use, encirclessome or all of eye 230. According to one embodiment, tube 120 ispositioned within the lumen of both legs 100A and 100B. In theembodiment shown, both ends of track 110 are accessible for coupling vialegs 100A and 100B.

Alternative materials and structures are also contemplated forintroducer 95A. For example, in one embodiment, introducer 95A isfabricated of a single formed tube rather than of two tubes. In oneembodiment, introducer 95A is fabricated of molded plastic materialhaving a pair of tubular guides arranged to facilitate introduction oftrack 110 as shown herein. In one embodiment, a single pneumaticcoupling is provided for inflating a balloon within track 110 and theballoon is deflated by removing the air pressure supply. In oneembodiment, plate 125 is secured to legs 100A and 100B by a mechanicalfastener or a soldered or brazed connection. In one embodiment,introducer 95A is fabricated of a plastic, synthetic or othernonmetallic material. In one embodiment, nipples 105 are omitted andtrack 110 is coupled directly to legs 100A and 100B.

In one embodiment, tube 120 is used to both position and inflate balloon115. In one embodiment, balloon 115 is joined or spliced onto tube 120by a heat shrink tubing, an adhesive or other coupling means. In oneembodiment, balloon 115 is molded into position during the fabricationprocess of tube 120. Balloon 115 can be positioned at an end of tube 120or positioned in the middle of tube 120. In one embodiment, tube 120 ispositionable within the lumen of track 110 and track 110 is covered withprotective sleeve 130.

FIG. 1B illustrates a top view of introducer 95A coupled to protectivesleeve 130 of track 110. Protective sleeve 130, in the figure, includesa transparent plastic tube. A slot in track 110 is not shown in FIG. 1B.In the figure, eye 230 is shown within the loop formed by sleeve 130.

In FIG. 2, introducer 95A is held in a position near the eye of a pigmodel. The figure illustrates relative sizes for one embodiment of thepresent subject matter.

In FIG. 3, introducer 95A is shown in a position in which track 110encircles the pig model eye. As shown, nipples 105 and track 110 arepositioned under the eyelids, and a portion of the introducer is locatedunder the lateral canthus and is therefore, not visible in the figure.

FIG. 4 illustrates a cross-section of a segment of a balloon in a lengthof tube 120 for use with the structure illustrated in FIG. 5. In FIG. 4,balloon 115 is fabricated of an elastic material such as rubber or latexand has a thin wall portion at 117. Thin wall portion 117 expands to alarger diameter when pressure is applied to the interior. For example,liquid or gas pressure may be applied to a first end of balloon 115 andvented or released at a second end of balloon 115. In one embodiment,balloon 115 includes a sealed envelope and pressure is applied andreleased from an orifice of balloon 115.

With respect to FIG. 5, a half section view of portions of track 110,according to one embodiment, is shown. In the figure, leg 100 isterminated with a nipple 105, herein illustrated as a bead or collar.Within leg 100 is track 110 having linear slot 135 of variable aperture.Track 110 is sheathed within the lumen of sleeve 130 and sleeve 130 isaffixed, by nipple 105, to leg 100. In the embodiment shown, leg 100 isfabricated of substantially rigid plastic or tubular shaped metal.Nipple 105, in one embodiment, includes a raised bead formed in the endof leg 100 or is fabricated of other material such as metal or plastic.Track 110 is fabricated of plastic such as Teflon® (E.I. du Pont deNemours and Company, Wilmington, Del.), polymeric compound or othersemi-rigid material. Sleeve 130 is fabricated of an elastic materialsuch as rubber, latex or other thin polymer and in the embodiment shown,is held in position by a friction fit over nipple 105. In oneembodiment, sleeve 130 is held in position by a length of heatshrinkable tubing.

In FIG. 5, tube 120 is disposed within track 110. Tube 120 includesballoon 115 and in the figure, balloon 115 is shown partially inflatedand located in a region not encompassed by slot 135. Further insertionof tube 120 into track 110 brings slot 135 and balloon 115 intoalignment.

In addition, the embodiment illustrated in FIG. 5 indicates that track110 is routed within the lumen of leg 100 and sleeve 130 is fitted overnipple 105. In contrast to the embodiment of FIG. 5, the embodiment ofFIG. 1B shows track 110 is fitted over nipple 105 and tube 120 ispositioned within the lumen of legs 100A and 100B. Other configurationsfor the relative orientation of coupling track 110, tube 120, sleeve 130and legs 100 are also contemplated.

Introducer 95A facilitates the installation of track 110 at a positionencircling at least a portion of the eye. Track 110 is positioned in amanner such that slot 135 is adjacent to the area of the eye that is tobe depressed. In one embodiment, slot 135 is of a length that encirclesa portion of the eye. In one embodiment, slot 135 is of a length thatencircles the eye one or more times. Multiple loops around eye 230permit a particular thruster to be positioned at one of two or morepositions along the longitudinal axis.

FIG. 6 illustrates an isometric view of a portion of track 110. Slot 135is visible in the figure and provides extension space into which balloon115 expands when inflated or otherwise pressurized. Thus, in oneembodiment, track 110 is aligned such that slot 135 is directed towardsthe longitudinal axis of the eye.

In FIG. 7A, sleeve 130 is illustrated having protective ends 133A and133B. Sleeve 130, in one embodiment provides a physical barrier betweenthin wall section 117 and the eye. Ends 133A and 133B, in oneembodiment, include heat shrinkable tubing. Tube 120 is illustrated tobe disposed in the lumen of track 110, which is also disposed in thelumen of sleeve 130, and extending beyond one end. In FIG. 7B, track 110is shown with a deployed thruster. In the figure, a pneumatic thrusteris pressurized and a thinned portion, such as shown at 117 (FIG. 4), hasexpanded, resulting in a raised portion of sleeve 130.

Sectional views of a balloon type thruster are shown in FIGS. 7C and 7D.In both FIG. 7C and FIG. 7D, the combination of track 110, tube 120 andsleeve 130 are positioned adjacent sclera 231 with the slot of track 110directed towards sclera 231. In FIG. 7C, balloon 115 is substantiallydeflated and thus occupies the lumen of track 110. Protective sleeve 130encases track 110. In FIG. 7D balloon 115 is inflated, as shown at cutline 7D-7D of FIG. 7B, and is forced out of the lumen by air pressure.Protective sleeve 130 expands to accommodate the increased size ofballoon 115. Sclera 231 is depressed in the region adjacent the slot oftrack 110.

In one embodiment, the dimensions of slot 135 are selected to allow athruster to exert a force to a predetermined portion of the eye. Aparticular width, length, placement, or shape of the aperture formed byslot 135 can be selected. In one embodiment, the aperture is circular oroval shaped. For example, with mature adults, a particular slot, oraperture dimension may be appropriate and for infants or youths, asmaller aperture may be appropriate for any given medical procedure.

In one embodiment, the amount of deployment, and thus, the force appliedby a balloon type thruster can be selected by choosing the placement anddimensions of an aperture in track 110. For example, a larger aperturewill allow a larger portion of a balloon to distend beyond the lumen oftrack 110.

In FIG. 8, processor 170 is coupled to track 110 by interface 180. Track110 includes one or more thrusters and one or more thruster positioningelements. Interface 180 includes hardware and programming to convert anelectrical signal to mechanical motion to operate a thruster or toposition a thruster. Processor 170 provides an electrical drive signalto interface 180. Processor 170 includes computer readable instructionsand has access to memory 175. In one embodiment, hand control 138 iscoupled to processor 170 and provides command signals for directing theoperation of track 110. In one embodiment, foot control 140 is coupledto processor 170 and provides command signals for directing theoperation of track 110. In one embodiment, audio control 165 is coupledto processor 170 and provides command signals for directing theoperation of track 110. In one embodiment, a hand control 138, footcontrol 140, or audio control 165, permits independent control of theposition of a thruster about the periphery of the eye as well as theamount of depression exerted by the thruster.

Hand control 138, in one embodiment, includes one or more user-operablecontrols for directing the operation of track 110. In one embodiment, ahand control includes a joy-stick type controller, a mouse, atouch-sensitive surface or one or more user-accessible switches.

Audio control 165, in one embodiment, includes a microphone, a processorand programming adapted to provide an electrical control signal based ona received verbal command. The control signal is received by processor170 and, after further processing, provides a drive signal to interface180.

Foot control 140, in one embodiment, includes one or more foot operableswitches and includes programming adapted to provide an electricalcontrol signal. The control signal is received by processor 170 and,after further processing, provides a drive signal to interface 180.

FIG. 9 illustrates foot controller 140 for operating a thrusteraccording to one embodiment. Housing 155 includes electrical circuitryand is coupled to processor 170 by cable 160. Foot controller 140includes positional switches 145A and 145B. When actuated, switches 145Aand 145B, in one embodiment, rotate a particular thruster about thelongitudinal axis in a clockwise and counter-clockwise direction,respectively. In one embodiment, positional switches 145A and 145Binclude toggle switches. Foot controller 140 also includes lineardisplacement switches 150A and 150B, actuation of which, in oneembodiment, causes a particular thruster to be deployed or retracted bya predetermined linear distance. In one embodiment, by depressing andholding a linear displacement switch, the thruster commences movementand proceeds to retract or deploy to a predetermined linear position. Inone embodiment, additional switches are provided to allow selectivecontrol over position and displacement of multiple thrusters.

FIG. 10 illustrates one embodiment of a thruster according to thepresent system. In the figure, a first end of arm 220A is rotatablycoupled to a boss secured to structure 210 and adapted to pivot aboutaxis 215A. In addition, a first end of arm 220B is rotatably coupled toa boss secured to structure 210 and adapted to pivot about axis 215B.The second end of arm 220A and the second end of arm 220B are rotatablycoupled to connecting link 235 and adapted to pivot about axis 225A andaxis 225B. Contacting arm 240, in one embodiment, is coupled toconnecting link 235. Contacting arm 240, in one embodiment, is coupledto arm 220B. Contacting arm 240 is brought into contact with eye 230 byapplying a force in the direction of arrow 200. In one embodiment, theforce is exerted by a rotating shaft coupled to a pivot axis such as215A, 215B, 225A or 225B. In one embodiment, the force is exerted by alinear force applied to any of arm 220A, 220B or link 235. Arms 220A and220B and link 235 are fabricated of a metal alloy or polymer material.

FIG. 11 illustrates one embodiment of a thruster according to thepresent system. In the figure, rotatable shaft 250 has external threadswhich engage corresponding internal threads of stationary nut 245.Protective cap 247 is fitted to one end of shaft 250 and is adapted tocontact the surface of eye 230. Cap 247, in one embodiment, isfabricated of a polymer and is adapted to rotate independent of shaft250. A rotational force applied in the direction of arrow 255 causesshaft 250 to withdraw from eye 230. A rotational force applied in theopposite direction of arrow 255 causes shaft 250 to approach eye 230,thus applying a depression force. Cap 247 is adapted to not rotate whenbrought into contact with eye 230. In one embodiment, shaft 250 issecured to prevent rotation and nut 245 is rotated to extend or retractshaft 250 relative to eye 230.

FIGS. 12, 13A and 13B illustrate embodiments having motive forcesderived from a fluid pressure. Fluid pressure includes pneumaticpressure or hydraulic pressure. Pneumatic pressure refers to a pressureof a gas, some examples of which include air or an inert gas. Hydraulicpressure refers to a liquid pressure.

FIG. 12 illustrates one embodiment of a thruster according to thepresent system. In the figure, pushrod 270 is adapted to be received byan interior cavity of cylinder 265. The exterior dimensions of cylinder265 are adapted to be received by an interior cavity of cylinder 260.Cylinder 260 is coupled to line 275A and line 275B. Cylinder 260,cylinder 265 and pushrod 270 are adapted for telescopic action. Whenpressure is applied using line 275B, cylinder 265 and pushrod 270 bothmove to an extended position. When pressure is removed from line 275A,cylinder 265 and pushrod 270 both move to a retracted position. In oneembodiment, lines 275A and 275B are adapted to accept pneumaticpressure. In one embodiment, lines 275A and 275B are adapted to accepthydraulic pressure.

FIGS. 13A and 13B illustrate an embodiment of a thruster according tothe present system. In FIG. 13A, for example, line 290 is coupled to apressure supply. Line 290, in one embodiment, is coupled to a gaspressure line. Line 290, in one embodiment, is coupled to a fluid line.The fluid line can carry hydraulic or pneumatic pressure. Valve 285 isshown in a closed position and thus, balloon 280 is unpressurized. InFIG. 13B, for example, valve 285 is shown in an open position and thus,balloon 280 is pressurized and a force is exerted on a portion of eye230. In one embodiment, a pair of lines are coupled to a balloon andpressurization of the balloon is controlled by introducing pressure viaone line and relieving pressure via a second line. Other means ofinflating, or pressurizing, a balloon are also contemplated.

FIG. 14 illustrates one embodiment of a thruster positioning systemaccording to the present subject matter. In the figure, eye 230 isencircled by driven ring 305. Driven ring 305 receives power fromdriving wheel 315 via cord 310. Driven ring 305 and driving wheel 315,in one embodiment, have a circumferential groove that receives cord 310.In one embodiment, teeth are located about the circumference of bothdriven ring 305 and driving wheel 315 and cord 310 includes a toothedbelt. Flexible shaft 325 supplies rotational power to driving wheel 315as illustrated, for example, by arrow 320. In one embodiment, a cordengages a take-up reel.

In one embodiment, one or more thrusters are coupled to driven ring 305.The radial position of the one or more thrusters is controlled byrotation of driven ring 305. In one embodiment, multiple concentricdriven rings encircle the eye and one or more driving wheels are used toselectively position a particular thruster.

FIG. 15 illustrates one embodiment of a thruster positioning systemaccording to the present subject matter. In the figure, eye 230 isencircled by ring gear 330. The sprockets of ring gear 330 engage pinion340. Pinion 340 is driven by motor 335. In one embodiment, motor 335includes a stepper motor. In one embodiment, pinion 340 is driven by aflexible shaft.

In one embodiment, a thruster is positioned by means of a frictiondrive. For example, a soft rubber wheel driven by a flexible shaft orstepper motor engages a ring encircling the eye. A thruster is coupledto the ring.

In one embodiment, one or more thrusters are coupled to ring gear 330.The radial position of the one or more thrusters is controlled byrotation of ring gear 330. In one embodiment, multiple concentric ringgears encircle the eye and one or more pinions are used to selectivelyposition a particular thruster.

FIG. 16A and FIG. 16B illustrate a thruster according to one embodiment.In FIG. 16A, for example, thruster arm 360 is in a retracted positionusing a solid line and thruster arm 360 is shown in an extended, ordeployed, position using a dashed line. Thruster arm 360 rotates aboutaxis 365 which is coupled to transmission housing 370 having input shaft375. In one embodiment, input shaft 375 is remotely accessible andallows control of the thruster. For example, thruster arm 360 can beradially positioned by pushing or pulling on shaft 375. In addition, arm360 can be extended or retracted laterally by rotating shaft 375. In oneembodiment, input shaft 375 is coupled to a mechanical drive system.Thruster arm 360, when retracted, is positioned within the lumen oftrack 110.

FIG. 16B illustrates apparatus for converting rotational forces on shaft375 to a thruster force exerted by arm 360. Shaft 375 is coupled to arm360 by driving bevel gear 380 and driven bevel gear 385. Othertransmissions or gear trains are also contemplated. In one embodiment,gears 380 and 385 are enclosed within housing 370.

FIG. 16C illustrates a thruster according to one embodiment. Thrusterarm 386 is depicted in the retracted position using a solid line and inthe extended position using a dashed line. Thruster arm 386 is coupledto guide 384 by resilient strip 383. In one embodiment, shaft 387extends beyond track 110 and is accessible externally. By pushing orpulling on shaft 387, thruster arm 386 can be positioned within track110. Shaft 387, in one embodiment, includes a flexible shaft and may befabricated of metallic or non-metallic material. Control line 388 iscoupled to a portion of arm 386 and, in one embodiment, passes through abore in guide 384, and extends beyond track 110 and is accessibleexternally. By pulling on control line 388, arm 386 is urged into anextended, or deployed position and when a pulling force is removed fromcontrol line 388, resilient strip 383 urges arm 386 into a retractedposition. In one embodiment, arm 386, guide 384 and resilient strip 383are configured to control movement of arm 386. In one embodiment,resilient strip 387 provides a return spring force to urge arm 386 intothe retracted position.

Resilient strip 383, in various embodiments, includes a metallic ornon-metallic leaf spring. In one embodiment, resilient strip 383includes a live hinge and is fabricated of a polymer material. Resilientstrip 383 is bonded or fastened to both guide 384 and arm 386. Controlline 388, in one embodiment, includes a monofilament or polyfilamentline.

FIG. 17 illustrates a thruster according to one embodiment. In thefigure, arm 400A, arm 400B and thruster shoe 415 are linked together atpivot 410. Arm 400A is also coupled, at pivot 405A, to shaft 390A. Arm400B is coupled, at pivot 405B, to shaft 390B. Shafts 390A and 390B aredisposed in the lumen of track 110 and are remotely accessible. Arrows420A and 420B indicate degrees of freedom for controlling the positionand deployment of shoe 415. Shoe 415 is deployed and retracted by travelshown generally at arrow 422. For example, when either shaft 390A orshaft 390B, or both shafts 390A and 390B, are displaced in a generallydownward direction, shoe 415 moves into a retracted position. Todisplace shoe 415 leftward in the figure, shaft 390A is displaceddownwardly and shaft 390B is displaced upwardly. By manipulating shafts390A and 390B, either independently or in combination, shoe 415 can bedisplaced radially as well as laterally. In one embodiment, shaft 390Ais coupled to arm 400A by a transmission and arm 400B follows the motionof arm 400A. Thus, rotational forces on shaft 390A are translated toextension or retraction forces on arm 400A.

In one embodiment, a position of a thruster is controlled by manuallymanipulating a control cable or other flexible shaft. In one embodiment,deployment of a thruster is controlled by manually manipulating acontrol cable or other flexible shaft. For example, with regard to theembodiment of FIG. 17, braided wire ropes or cables coupled to shaft390A and shaft 390B allow positioning of thruster shoe 415. In oneembodiment, by pushing or pulling along the axis of the control cable,the position of a thruster can be adjusted or deployment of a thrustercan be controlled. In one embodiment, rotation of the control cableadjusts the position of a thruster or deployment of a thruster.

FIG. 18 illustrates a thruster according to one embodiment. In thefigure, arm 425 terminates with foot 430. Foot 430 can be positioned toexert a depression force on the eye. In one embodiment, arm 425 can bemanipulated, by rotation, as indicated by arrow 445, to exert ananterior, posterior or circumferential force on the eye. In addition,the elastic properties of arm 425 allow manipulation in directions asindicated by arrow 440. Arm 425 is accessible outside of the lumen oftrack 110. In one embodiment, arm 425 is fabricated of shape memorymetal or shape memory material. Arm 425, in one embodiment, is adaptedto retract into the lumen of track 110.

In one embodiment, super elastic properties of arm 425 allow specificthrust to be applied at a targeted area. For example, arm 425 can berotated to exert thrust at a particular angle. In one embodiment, arm425 is adapted to retract into the tube encircling the eye. Foot 430 canbe deployed at a selected angle and can rotate anteriorly, posteriorlyor circumferentially.

FIGS. 19A and 19B illustrate a cam operated thruster according to oneembodiment. In the figure, thruster arm 465 is shaped to interface witha contour of cam 470. Cam 470 is remotely operable by way of shaft 475.Thruster arm 465 is linked to guide 460 at pivot 455. Cam 470 and guide460 are sized to slidably fit within the lumen of track 110. Guide 460is remotely operable by way of shaft 450. In FIG. 19A, thruster arm 465is illustrated in a retracted position.

In FIG. 19B, thruster arm 465 is extended. In the figure, cam 470 andguide 460 have converged and a contour of cam 470 has forced thrusterarm 465 into an extended position. A spring, or other force, acting onthruster arm 465 urges retraction of thruster arm 465 into the lumen oftrack 110. In one embodiment, a spring urges deployment of a thruster.Shafts 475 and 450 can be remotely manipulated to cause thruster arm 465to be deployed at a particular location along the length of track 110.By adjusting the relative position of cam 470 and guide 460, the degreeof extension or retraction of thruster arm can be controlled.

FIG. 20 illustrates a thruster according to one embodiment. In thefigure, shaft 530 is coupled to guide 525. Guide 525 is coupled to afirst end of arm 505 at pivot 520. Arm 505 is also coupled to a firstend of arm 495 at pivot 500. A second end of arm 495 is coupled to guide485 at pivot 490. Guide 485 is coupled to shaft 480. Guides 525 and 485are sized to fit within the lumen of track 110. Shafts 480 and 530 areremotely accessible. A shaped end of arm 505 is adapted to exert a forceon the eye. Arm 505 and arm 495, in one embodiment, have a curved shapewith arm 505 longer than arm 495.

Arm 505 is retracted by increasing the distance between guide 525 andguide 485. Arm 505 is extended, or deployed, by reducing the distancebetween guide 525 and guide 485. In one embodiment, the radial positionof the thruster in FIG. 20 is controlled by coordinated movement ofguide 485 and guide 525.

To use one embodiment of the present subject matter, the track isassembled to the introducer. In assembling the track, a suitableremotely controlled drive is connected to any guides or shafts. Theremotely controlled drive may include pneumatic, hydraulic or mechanicalcouplings. The track is then positioned about the eye using theintroducer or other means of positioning. A thruster is positioned on,or within, the track at a desired location using the thrusterpositioning device. In one embodiment, a radial position for a thrusteris selected after which the thruster is deployed. In one embodiment, aselected thruster is deployed and subsequently re-positioned. In oneembodiment, multiple thrusters are independently positioned anddeployed. In one embodiment, the track is placed within the bony orbitwithout the aid of introducer 95A.

In one embodiment, a light source, or illumination source, is positionedwithin track 110 to provide transcleral illumination. FIG. 21illustrates an embodiment having two filaments within the lumen of track110. In the figure, filament 560A and filament 560B are positionedalongside of balloon 115. In one embodiment, a single filament isdisposed within the lumen of track 110. In one embodiment, a pluralityof filaments are disposed within the lumen of track 110. In oneembodiment, a filament is disposed within the lumen of balloon 115. Inone embodiment, track 110 is fabricated of a transparent or translucentmaterial. In one embodiment, protective sleeve 130 (not shown in thefigure) is fabricated of transparent or translucent material. In oneembodiment, the filament is positioned within track 110 by one of thesystems and methods described elsewhere in this document. In oneembodiment, an illumination source is disposed within a lumen of tube120.

Each filament includes an optical element fabricated of glass or plasticand is sometimes referred to as a fiber optic filament. The filament issufficiently flexible to conform to the routing of track 110. In oneembodiment, the illumination source, filament, or light pipe, providesside illumination (side emitting). A coating on the filament allowslight to diffuse from a side. When positioned around the eye, the sideemitting light pipe provides diffuse illumination of the sclera.

In one embodiment, the illumination source or filament provides endillumination (end emitting). An end of the filament is treated toenhance light scattering. In one embodiment, the end is cutperpendicular and can be modeled as a point light source.

In one embodiment, an end emitting filament can be positioned withintrack 110 at a location independent of a thruster or balloon. In oneembodiment, an end emitting filament is coupled to a thruster or balloonand is positioned within track 110 coincident with the positioning ofthe thruster or balloon. For example, in one embodiment, an end emittingfilament is radially positioned to provide lighting opposite theposition of the thruster or balloon. Multiple end-emitting filaments canbe positioned within track 110. In one embodiment, an end emittingfilament is positioned near one or both nipples of introducer 95A.

The filament is illuminated by remote light source 570 coupled tofilament 560 as shown in FIG. 22. The remote light source includes acoupling to interface the filament with a light source. In oneembodiment, the light source includes a plurality of light emittingdiodes (LEDs). In one embodiment, the light source includes a halogenlamp.

In one embodiment, a track 110 or tube 120 is fabricated of materialthat provides illumination of selected portions of the eye. For example,in one embodiment, the track or tube includes a side emitting opticalelement that provides diffuse or focused lighting at a selected regionof the eye. In one embodiment, the track is fabricated of a translucentmaterial that conducts light to a particular portion. The light can bepositioned or focused to illuminate a selected portion.

Alternative Embodiments

Variations of the above embodiments are also contemplated. For example,in one embodiment, a foot control or audio control allows operatorselection of a thrust axis. The thruster can be configured to exertthrust along an axis normal to the longitudinal axis or at a particularangle to the longitudinal axis. For example, by rotating track 110, slot135 can be repositioned and thus, balloon 115 exerts thrust at aselected angle to the longitudinal axis of the eye.

In one embodiment, a hydraulic or pneumatic force is used to positionthe thruster. For example, the thruster is coupled to a diaphragm orpiston and hydraulic or pneumatic pressure (or vacuum) is applied to oneend of a double acting cylinder. A double acting cylinder includes ashaft that extends from one end of a cylinder and is connected to adiaphragm or piston that moves in either direction within the cylinderunder hydraulic pressure. Movement of the diaphragm or piston causes thethruster to be repositioned relative to the track. In one embodiment,the hydraulic fluid includes a saline solution.

In one embodiment, a thruster is coupled to a cable operated piston.Movement of the cable causes the thruster to be repositioned relative tothe track. In one embodiment, a cord, filament, belt or other flexibledevice is used to position the thruster.

In one embodiment, a thruster can be positioned along one of two or moretrack segments that encircle the eye. For example, in one embodiment, atrack includes a first loop and a second loop, as illustrated in FIG.23, thus permitting depression of multiple anterior-posterior locationsradially in the peripheral retina. As shown in the figure, track 110includes an anterior portion 113A and a posterior portion 113B. Anteriorportion 113A provides access to the pars plana region of eye 230, andposterior portion 113B provides access to the posterior vitreous basefor surgery involving retinal detachment tears and circumferentialcontracture of the vitreous. Slot 135 is oriented towards the eye in thefigure.

In the figure, anterior portion 113A and posterior portion 113B arecontiguous. In one embodiment, anterior portion 113A is discontinuouswith posterior portion 113B. In one embodiment, two or more portions ofa track are provided. In one embodiment, multiple loops around the eyeare sheathed in a single protective sleeve.

In one embodiment, the thruster is supported by the bony orbit of theeye and the track is captivated by the anterior orbital rim. In oneembodiment, a bridge assembly couples the introducer to the nose of apatient. In one embodiment, the track and thruster are adapted forattachment to the blade of an eyelid speculum. In one embodiment, thetrack and thruster are integrated with an eyelid speculum. In oneembodiment, clips or mechanical fasteners are provided to allowattachment of the thruster to a lid speculum.

FIG. 24 illustrates one embodiment of an introducer integrated with aspeculum. In the figure, introducer 95B includes a pair of formedtubular legs held in rigid alignment by a joining strut. The legs ofintroducer 95B are configured to facilitate introduction of track 110about the bony orbit of an eye, and in the embodiment shown, the legs donot cross each other. Blades 590A and 590B are coupled to speculum legs585A and 585B, respectively, and formed to hold the eyelids in a fixedposition. Speculum legs 585A and 585B, in one embodiment, are fabricatedof spring steel. Blades 590A and 590B are fabricated of wire stock.Joint 580, in one embodiment, includes a threaded fastener that couplesspeculum legs 585A and 585B to the strut of introducer 95B. In oneembodiment, joint 580 includes a flexible coupling that allows legs 585Aand 585B to be positioned at an angle relative to introducer 95B. Invarious embodiments, joint 580 includes a ball and socket joint, auniversal joint, a plastic hinge joint or other coupling allowingintroducer 95B to be positioned without interfering with the placementof blades 590A and 590B. A spring wire-type speculum is illustrated,however, other types of specula are also contemplated.

In various embodiments, joint 580 includes coupling that allows thespecula to be quickly affixed to the introducer without the use oftools. For example, in one embodiment, the joint includes fittings onthe specula and the introducer which allows the specula to be clippedinto position on the introducer during the course of a surgicalprocedure. In one embodiment, the joint includes a fastener or clip atan edge (or surface) of the strut and a matching fastener or clip on thespecula. In one embodiment, the specula is positioned substantiallyunderneath the introducer. In one embodiment, the introducer ispositioned substantially underneath the specula.

In one embodiment, a bell crank assembly is coupled to the thruster.FIG. 25 illustrates thruster 360 adapted to pivot on a shaft and coupledto concentric sprocket 540. Sprocket 545 engages the teeth of sprocket540 and is rigidly coupled to bell crank 550. Bell crank 550 is coupledto line 555A and line 555B. A suitable force applied to line 555A orline 555B will deploy or retract thruster 360.

In one embodiment, line 555A includes a rigid shaft and line 555B isomitted. A force applied to line 555A will deploy or retract thruster360.

In one embodiment, the thruster includes a flexible tip or contactsurface.

In one embodiment, each thruster, of a plurality of thrusters, isindependently retractable or deployable. In one embodiment, eachthruster can be positioned independent of the position of otherthrusters. In one embodiment, the degree of extension or retraction ofeach thruster can be independently selected.

In one embodiment, a transcleral light source is positioned around theeye using track 110 and introducer 95A and no thruster or balloon isincluded in track 110.

In one embodiment, track 110 includes an endless loop and a ring gear orother structure within track 110 is used to position a thruster.

In one embodiment, introducer 95A facilitates insertion of a partialloop of track 110 about the bony orbit.

FIG. 26 illustrates one embodiment of the present subject matterincluding fiber optic element 560 configured to illuminate balloon 115.End 561 of fiber optic element 560 is coupled to a light source.Coupling 615, in one embodiment, includes a heat shrink tubing thatrigidly affixes fiber optic element 560 to port 621 of three-portfitting 620. Port 622 is coupled to Teflon® tube 562 by coupling 610A.Port 623 is coupled to a pressure source for controlling inflation anddeflation of balloon 115. Fiber optic element 560 is positioned withintube 562 and terminates at end 605 within balloon 115. Coupling 610Bcouples tube 562 to a first stem of balloon 115. A second stem ofballoon 115 is sealed closed.

Fiber optic element 560, in one embodiment, includes a side emittingelement. End 605 is adapted to disperse light from within element 560.In one embodiment, end 560 includes a generally spherical shape formedby heating and molding.

End 605 is held in position within balloon 115 by the structuredescribed herein and, in one embodiment, aids in positioning the balloonat a point for application of a thrusting force.

Balloon 115 is spaced apart from fitting 620 by a sufficient dimensionsuch that balloon 115 can be suitably positioned to apply pressure tothe sclera as described herein. In one embodiment, fitting 620 isexternal to the bony orbit and balloon 115 is within the bony orbit. Inone embodiment, fitting 620 is a straight coupling with no “T”connection, or port, as shown at 623, and a source of air pressure isinjected into balloon 115 at coupling 615.

FIG. 27A illustrates a portion of an embodiment having balloon 115Adisposed in track 110. As shown in the figure, when balloon 115A isinflated, portions of the balloon stems are drawn out of the slot oftrack 110. FIG. 27B illustrates an embodiment wherein balloon 115B isadapted such that the stems remain wholly within the lumen of track 110.In FIG. 27B, the stems of balloon 115B are coupled to the sphericalportion at a location offset from a centerline of the balloon.

Other methods of retaining balloon stems within the lumen of track 110are also contemplated. For example, in one embodiment, an adhesivecoating is applied to a backside portion of balloon 115 to restrictinflation of that portion, thereby shifting a greater amount ofdisplacement to other portions of the balloon. In one embodiment, thewall thickness of balloon 115 is molded to force inflation to be greaterin one dimension as compared to another dimension. In one embodiment, anouter sleeve with a hole is positioned over balloon 115, therebycontrolling the direction of inflation.

FIG. 28 includes a section view of fiber optic element 560 according toone embodiment. Exposed region 655 is devoid of cladding 650 and thus,light within element 560 will be projected at a greater intensity fromregion 655. In one embodiment, at region 660, a light reflective coatingis applied to direct illumination into region 655.

FIG. 29 includes a continuous loop of side emitting fiber optic element561. Element 561 includes a shaped portion 563 adapted to provideadditional illumination, as denoted by the relative sizes of arrowsdistributed about element 561. Light source 571 illuminates both ends ofelement 561. In one embodiment, portion 563 is fabricated by heating andexerting a compressive force on each end to form a thickened, orgenerally spherical region along the length of element 561. Portion 563,in one embodiment is aligned with the center of balloon 115 to aid inplacement of balloon 115 within the track.

FIG. 30A includes an embodiment for immobilizing the present subjectmatter within the bony orbit of an eye. In the figure, tube 680 includesfirst lumen 684 and second lumen 682. Second lumen 682 is adapted toreceive a fiber optic element, a balloon or other thruster device asdescribed herein. First lumen 684 is adapted to receive flat spring685A. Flat spring 685A, in the figure, has a “D” shape cross section andis adapted to urge tube 680 in a direction towards an increased majordiameter, thus applying a greater holding force within the bony orbit.In various embodiments, spring 685A includes a metal leaf spring, ashape memory material, a coil spring, a non-metallic spring or othermaterial or structure.

In one embodiment, the track is fabricated with structure to aid inimmobilizing the track within the bony orbit. In one embodiment, thestructure includes a series of ribs, knobs or other raised portions toimprove the grip with the bony orbit.

FIG. 30B includes a section view of tube 700 and formed ridges 705.Spring 685B is captivated by the wall of tube 700 and ridges 705. In oneembodiment, a spring fits within linear grooves on the inside surface oftube 700.

In one embodiment, undesirable heating from the fiber optic element canbe ameliorated by circulating cooling air through the track of thepresent subject matter. Cooling air can be circulated by a vacuum orpressure system coupled to an end of the track. In one embodiment, acooling fluid, such as a saline solution or water, is circulated.

In one embodiment, an end emitting fiber optic element is positionedwithin balloon 115. The end of the element is polished or shaped to aidin readily identifying the position of the balloon during a surgicalprocedure.

CONCLUSION

The above description is intended to be illustrative, and notrestrictive. Many other embodiments will be apparent to those of skillin the art upon reviewing the above description.

1-33. (canceled)
 34. A method comprising: positioning a guide memberaround at least a portion of an eye, the guide member providing accessto at least a first region of the eye, the first region disposedradially about the eye; positioning a first thruster independent of thepositioning of the guide member, the first thruster positioned proximateto the first region; and actuating the first thruster to exert a firstforce on the eye at the first region, the first force relative to theguide member.
 35. The method of claim 34 further comprising: positioninga second thruster relative to the guide member at a second regiondisposed radially about the eye; and actuating the second thruster toexert a second force on the eye at the second region, the second forcerelative to the guide member.
 36. The method of claim 35 whereinpositioning the second thruster is independent of positioning of thefirst thruster.
 37. The method of claim 35 wherein actuating the secondthruster is independent of actuating the first thruster.
 38. The methodof claim 34 wherein positioning the guide member includes at least oneof any combination of encircling at least a portion of the eye andpositioning within a bony orbit of the eye.
 39. The method of claim 34wherein positioning the first thruster includes at least one of anycombination of exerting a linear force about the eye and receiving asignal from a remote controller.
 40. The method of claim 34 whereinactuating the first thruster includes at least one of any combination ofreceiving a signal from a remote controller, exerting a linear forceabout the eye, introducing a fluid to an envelope, pumping a fluid intoa balloon, articulating a link arm, transforming a shape memorymaterial, exerting a spring force and selecting a radial extensiondimension.